1. Field of the Invention
The present invention relates generally to a sensor module. In particular, the present invention relates to a sensor module used for an electronic throttle device.
2. Description of Related Art
Conventional technologies will be described below. Conventionally, an electronic throttle device that controls a flow rate of intake air flowing in the inside (throttle bore) of a throttle body, which is incorporated along an intake pipe of an internal combustion engine (engine), by opening and closing operations of a throttle valve, is widely known. A sensor module that detects an opening degree of the throttle valve is disposed at the throttle body which accommodates the throttle valve (see, for example, JP-A-2004-004114 corresponding to U.S. Pat. No. 6,407,543 B1). The sensor module includes a throttle opening degree sensor that has a Hall IC for outputting an electrical signal corresponding to a density of magnetic flux released from a magnet rotor, which rotates together with the throttle valve; and a sensor cover made of insulating resin (insulating material) that has a connector, which holds the throttle opening degree sensor and connects with an external device.
Connector terminals that constitute a sensor connector wire of the throttle opening degree sensor are inserted (embedded and held) into the sensor cover. Connector end terminals projecting into the inside of a housing of the connector are formed on one end sides of the connector terminals. A connecting terminal, which is electrically connected and joined to a sensor lead terminal of the Hall IC, is formed on the other end sides of the connector terminals. The sensor module described in JP-A-2004-004114 is capable of preventing misalignment of a positional relationship between the magnet rotor fixed to a shaft of the throttle valve, and the throttle opening degree sensor held by the sensor cover. Accordingly, the sensor module can detect with high accuracy the degree of opening of the throttle valve (rotation information of the throttle valve) which is a detection object.
Defects of the conventional technologies will be described below. However, in the case of the sensor module described in JP-A-2004-004114, another sensor cover having a different shape from the present sensor cover may be produced due to, for example, constraints on the position for disposing the module. For example, if the sensor cover, with a direction of the connector, i.e., projecting direction (connector connecting direction) of the connector end terminal of the connector terminal reversed, is additionally produced, the shape of the end terminal of the connector terminal needs to conform to the shape of the additional sensor cover. Since the connector terminal having the end terminal in a shape that is in accordance with the shape of the additional sensor cover needs to be newly provided, the production costs for the connector terminal will increase as a result of the newly provided connector terminal. Moreover, because the sensor connector wire from the connector to the throttle opening degree sensor is configured by the connector terminal, which is an integral part, the connector terminals cannot easily be two-level crossed thereby to lower a degree of flexibility in wiring for an inner surface shape of the sensor cover.
The production costs of the connector terminal may be reduced by making employable one type of the connector terminal with its end terminal in the same shape commonly for more than one type of the sensor covers having different shapes from each other. However, a shape having a difference in height (level difference) on an inner surface of the sensor cover, which is currently incorporated into the sensor module (present sensor cover), is used for the present sensor cover. Therefore, a level difference is provided also for the connector terminal in conformity with the shape of this sensor cover. Thus, if the connector terminal is used with its surface having front and rear sides reversed, the shape of the sensor cover and the shape of the connector terminal do not conform with each other, so that the above-described proposal is not introducible. Furthermore, if the connector terminal is formed into a flat surface shape without a level difference in order to conform the shape of the sensor cover to the shape of the connector terminal, the size of the connector becomes larger than the size of the sensor cover. Consequently, the size of the entire sensor module is made large, so that it may be difficult to ensure a space for disposing the module.
A connector-integrated electronic circuit, in which a connector terminal is inserted into a connector housing, is described in JP-A-H09-017514. In the connector terminal, a component attachment portion for attaching an electronic component and a connector terminal portion for connection to an external circuit are connected and integrated in their length direction. According to this circuit, since the long connector terminal is inserted into the connector housing, there is a concern that the connector terminal cannot be set in an orderly fashion in a resin molding die for insert molding, due to a manufacturing variation of the connector terminal. In addition, the connector terminal is deformed at the time of insert molding into the connector housing, and the size of the connector-integrated electronic circuit thereby becomes nonstandard to increase its level of defectiveness. As a result, there is a problem of the decreased productivity.